Dust migration and distribution characteristics under different cutting paths in a fully mechanized excavation face

To investigate the effects of different cutting paths on dust migration and distribution in a fully mechanized excavation face, the fully mechanized excavation face II853 of Zhuxianzhuang Coal Mine, Huaibei Mining Co., Ltd., was selected as the study object. Numerical simulations of dust migration and distribution under four cutting paths were conducted using Fluent software. The results showed that: ① under the long-forcing short-exhaust ventilation mode, the airflow field in the fully mechanized excavation face could be divided into three characteristic regions along the roadway: a turbulent region (0–10 m), a transition region (10–40 m), and a stable region (40–60 m). A small-scale, high-velocity local vortex formed in the central area within 10 m of the working face, whereas a large-scale, low-velocity vortex formed within 20 m behind the exhaust outlet. ② Significant differences were observed in the spatial distribution and temporal evolution of dust under different cutting paths. Under the "center-first, periphery-later" cutting path, the dust concentration exhibited a distribution pattern of "higher near the floor and lower near the roof", and the dust concentration at the breathing zone fluctuated slightly over time with good stability. Under the "bottom-up" cutting path, the dust concentration showed a distribution pattern in which the breathing zone had the lowest concentration, while the concentrations near the floor and roof were nearly the same. In addition, the dust concentration at the breathing zone fluctuated markedly over time and exhibited poor stability. ③ The degree of matching between the cutting path and the airflow field significantly affected the dust concentration and distribution within 20 m of the working face. However, as dust particles migrated downstream along the roadway, the airflow field gradually became stable, and the dust distribution under different cutting paths tended to converge.